Hello,
I don’t see any issue with your contact-form.php. Seems you have a server side issue returning error 500 in all PHP files. The same occurs with the mailchimp/newsletter script:
https://infowebvalue.com/php/newsletter-subscribe.php
And that’s reason mailchimp newsletter it’s not working (the same reason for contact form).
This case you should check the error logs in your server to see what’s causing the error 500. My suggestion for you is contact your hosting provider support.
We hope this helps!
Please try that and le us know if you need further assistance.
Kind Regards,
Rodrigo.
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